An Apple laptop sits in a podium with the Google logo during a Google special event on September 8, 2010 in San Francisco. (Justin Sullivan/GETTY IMAGES)

Lawmakers pressed representatives from Apple and Google to explain their privacy policies Tuesday, questioning whether the companies’ practices ensure that mobile-phone users control their personal data.

“I believe that consumers have a fundamental right to know what data is being collected about them,” Sen. Al Franken (D-Minn.) said at a hearing of the new Senate Judiciary subcommittee on privacy, technology and the law. “I also believe that they have a right to decide whether they want to share that information, and with whom they want to share it and when.”

Franken, who chairs the subcommittee, asked Apple and Google to testify after researchers found a file containing unencrypted location data on Apple’s mobile devices last month.

Apple’s software chief, Guy “Bud” Tribble, said the company is committed to user privacy. “Apple does not track users’ locations,” he said. “Apple has never done so and has no plans to ever do so.”

Alan Davidson, Google’s director of public policy in the Americas, said the company’s Android smartphone platform has a similar policy. “All location data that is sent back to Google’s location servers is anonymized and is not traceable to a specific user or device,” he said.

But Franken challenged the assertion that Apple’s and Google’s location data are anonymous. He asked another witness, researcher Ashkan Soltani, if the time-stamped location data could be used to track users. Soltani said he thought it was possible and that claims the data are anonymous are “not really sincere.”

Lawmakers also expressed concerns about how mobile applications share data. Franken asked whether Google and Apple would create rules for their mobile stores, requiring developers to have a written privacy policy.

Neither Tribble nor Davidson responded directly. Davidson deferred to Google’s leadership to comment on such a policy. Tribble said privacy should be built in to applications, as many users do not read privacy policies.

In the end, few committee members seemed satisfied that current privacy law and industry practices adequately protect consumer privacy rights.

“I still have serious doubts that those rights are being respected in law or in practice,” Franken said in closing. “We need to think seriously about how to address this problem, and we need to address this problem now.”